Wheel end assembly high-temperature warning system

ABSTRACT

The present invention is directed to a wheel end assembly having a high temperature warning system for giving a warning in the event that the temperature in the assembly reaches a predetermined value such as caused by hub bearing failure or a brake related failure. In one embodiment the system may be a stand-alone system for installation on any vehicle such as a trailer. In another embodiment the system may be combined with an automatic tire inflation system.

This application is a Continuation of U.S. patent application Ser. No.13/435,924 filed Mar. 30, 2012, which is a divisional of U.S. patentapplication Ser. No. 12/166,123 filed Jul. 1, 2008, which issued as U.S.Pat. No. 8,186,403, which is a continuation of U.S. patent applicationSer. No. 11/039,551 filed on Jan. 20, 2005, which issued as U.S. Pat.No. 7,416,005, which is a continuation of U.S. patent application Ser.No. 10/657,886 filed on Sep. 9, 2003, which issued as U.S. Pat. No.6,892,778, entitled “Wheel End Assembly High-Temperature WarningSystem”, all of which are hereby incorporated in their entirety byreference. The present invention is directed to a wheel end assemblyhaving a high temperature warning system for giving a warning in theevent that the temperature in the assembly reaches a predetermined valuesuch as by a hub-bearing failure or brake related failure. The systemmay be a stand-along system for installation on any vehicle such as atractor trailer or in another embodiment may be a system combined withan automatic tire inflation system.

BACKGROUND OF THE PRESENT INVENTION

In the event of a wheel end assembly hearing failure or brake relatedfailure on a vehicle such as a tractor trailer, the temperature in theassembly and axle spindle area can reach a temperature to where thetires or lubricant may ignite causing the vehicle to burn or the wheelto lock up. It is also the possibility, due to the intense heat causedby any failure that the wheel can detach from the axle.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to a high temperature warning systemfor a wheel end assembly in which the vehicle has an air pressure supplyby providing a heat sensitive control mounted adjacent the wheelassembly for measuring the temperature of the wheel assembly andcontrolling a normally closed valve connected between the inside andoutside of the air pressure supply. A warning system is connected to thepressure supply for actuation on opening of the valve upon apredetermined temperature in the wheel area.

A further object of the present invention is the provision of a wheelend assembly having a high temperature warning system including an airpressure supply, a normally closed valve connected between the insideand outside of the pressure supply, a heat sensitive control connectedto and actuating the valve upon a predetermined temperature in which thecontrol is mounted adjacent the wheel assembly for measuring thetemperature of the wheel assembly, and a warning system connected to thepressure supply for actuation upon opening of the valve.

A still further object is wherein the heat sensitive control includes aheat sensitive pressure barrier. In one embodiment the heat sensitivepressure barrier is a fusible plug and may include an eutectic alloy.

Still a further object of the present invention is wherein the airpressure supply includes a hollow wheel axle closed at its ends with aplug. In one embodiment the heat sensitive pressure barrier ispositioned in each plug. In another embodiment one or more heatsensitive pressure barriers are positioned in the axle adjacent thebearings or brakes in the wheel assembly. In another embodiment, the airpressure supply includes air supply tubing positioned in the wheel axleand connected to one or more heat sensitive pressure barriers. Inanother embodiment, the heat sensitive pressure barriers are positionedadjacent the wheel bearings and brakes.

And still a further embodiment, the air pressure supply may include anautomatic tire inflation system for providing air to a rotating tire ona wheel hub mounted on bearings on a hollow axle connected to the airsupply for receiving air, and a rotary connection between the tire andthe axle.

Still a further object of the present invention is in which a vehiclehaving an automatic tire inflation system, is for providing air to arotating tire on a wheel hub mounted on bearings on a hollow axle, isconnected to an air pressure supply for supplying air to the inside ofthe axle, a rotary connection in communication between the tire and theair inside of the axle, of the combination of a high temperature warningsystem comprising a normally closed valve connected between the insideand outside of the axle in communication with the air in the axle. Aheat sensitive control is connected to and actuating the valve open upona predetermined temperature and said control is mounted adjacent thewheel assembly for measuring the temperature of the wheel assembly andaxle, and a warning system is connected to the air supply for actuationupon opening of the valve. In one embodiment the hollow axle is closedat the ends with a plug and a heat sensitive pressure barrier ispositioned in each plug. As an alternative, one or more heat sensitivepressure barriers may be positioned in the axle adjacent the bearings orbrakes in the wheel assembly. And in another alternative the airpressure supply includes an air supply tubing positioned in the axle andconnected to one or more heat sensitive pressure barriers. Again, thepressure barriers may be positioned in a plug at each end of the hollowaxle or positioned adjacent the wheel bearings and brakes are connectedin the axle.

The foregoing has outlined rather broadly the features and technicaladvances of the present invention in order that the detailed descriptionof the invention that follows may be better understood. Additionalfeatures and advantages of the invention will be described hereinafterwhich form the subject of the claims of the invention. It should beappreciated by those skilled in the art that the conception and specificembodiment disclosed may be readily utilized as a basis for modifying ordesigning other structures for carrying out the same purposes of theinvention. It should also be realized to those skilled in the art thatsuch equivalent construction do not depart from the spirit and scope ofthe invention as set forth in the appended claims. The novel featureswhich are believed to be characteristic of the invention both as to itsorganization and method of operation, together with further objects andadvantages will be better understood from the following descriptionswhen considered in connection with the accompanying figures. It is to beexpressly understood, however, that each of the figures is provided forthe purposes of illustration and description only and is not intended asa definition of the limits of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, reference isnow made to the following descriptions taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a schematic perspective elevational view, partly in crosssection, illustrating one form of an axle of a vehicle having a hightemperature warning system connected to the wheel assemblies;

FIG. 2 is an enlarged elevational view, in cross section, taken alongthe line 2-2 of FIG. 1 illustrating a wheel assembly and a hightemperature warning system;

FIG. 3 is a view similar to FIG. 2 illustrating another form of thepresent invention;

FIG. 4 is a view similar to FIG. 2 illustrating still another embodimentof the present invention;

FIG. 5 is a view similar to FIG. 2 illustrating still another form ofthe present invention;

FIG. 6 is an elevational cross-sectional view of a portion of anautomatic tire inflation system connected to an axle and providing ahigh temperature warning system;

FIG. 7 is an elevational view, in cross section, illustrating a partialof an automatic tire inflation system with other forms of hightemperature warning systems;

FIG. 8 is an elevational view in cross section of a part of an automatictire inflation system showing another form of a temperature warningsystem;

FIG. 9 is an elevational view, in cross section, showing a part ofanother automatic tire inflation system having another form of a hightemperature warning system.

FIG. 10 is a schematic perspective elevational view, partly in crosssection, illustrating an embodiment of an axle of a vehicle having ahigh-temperature warning system.

FIG. 11 is an enlarged elevational view, in cross section, taken alongthe line 2-2 of FIG. 11 illustrating a wheel-end assembly and ahigh-temperature warning system.

FIG. 12 is a view similar to FIG. 11 illustrating another embodiment ofa wheel-end assembly high-temperature warning system.

FIG. 13 is a view similar to FIG. 11 illustrating still anotherembodiment of a wheel-end assembly high-temperature warning system.

FIG. 14 is a view similar to FIG. 11 illustrating another embodiment ofa wheel-end assembly high-temperature warning system.

FIG. 15 is an elevational cross-sectional view of a portion of anautomatic tire inflation system connected to an axle and anotherembodiment of a wheel-end assembly high-temperature warning system.

FIG. 16 is an elevational view, in cross section, illustrating a part ofan automatic tire inflation system with another embodiment of awheel-end assembly high-temperature warning system.

FIG. 17 is an elevational view in cross section of a part of anautomatic tire inflation system showing another embodiment of awheel-end assembly high-temperature warning system.

FIG. 18 is an elevational view, in cross section, showing a part ofanother automatic tire inflation system having another embodiment of awheel-end assembly high-temperature warning system.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIGS. 1 and 2, the reference numeral 10 generallyindicates the high temperature warning system of the present inventionas installed in a vehicle having an axle 12 and a spindle 13 portionthereof. A wheel assembly 11 includes a hub 14 which rotates on innerand outer bearings 16 and 18, respectively, which rotate on inner andouter bearing races, respectively, 20 and 22, and extends through abrake drum 24 and supports a tire and wheel 26. As has been indicated inthe event of a bearing 16 or 18 or a brake 24 failure, the temperaturein the bearings 16 and 18, the brake drum 24 and spindle 13 area mayreach a temperature to where the tires (not shown) on the tire and wheel26 or lubricant (not shown) may ignite causing a fire. There is also thepossibility because of the intense heat caused by such failures that thehub 14 and wheel and tire 26 may detach from the axle 12.

The temperature warning system 10 of the present invention includes anair pressure supply 28 which is a normal component on a truck or vehiclefor various purposes such as brakes, a pressure protection valve 30, aflow switch 32 and an indicator or warning system light 34. The airpressure supply preferably includes the axle 12 which is hollow and isconnected to supply 28 through line 36 and includes an internal plug 37at each end of the axle 12 whereby the interior of the axle 12 formspart of the air pressure supply.

One or more normally closed valves 38 and 40, (FIG. 1) such as heatsensitive pressure barriers 38′ and 40′ (FIG. 2) comprising a fusibleplug 38′ and 40′ (FIG. 4), are connected between the inside 42 and theoutside 44 of the pressure supply. The heat sensitive pressure barriers38′ and 40′ are fusible plugs 38″ and 40″ which also form a heatsensitive control for actuating the opening and closing of the valves 38and 40 upon a predetermined temperature. Thus, when the area in whichthe plugs 38″ and 40″ are installed reaches a certain temperature thealloy will melt, creating an air leak from the air supply tank 28. Thiswill be detected by the flow switch 32 which actuates the warning systemlight 34 which is positioned adjacent the driver of the vehicle toindicate a problem. The heat sensitive pressure barriers 38′ and 40′ aremounted adjacent to the wheel assemblies 11 for measuring thetemperature of the wheel assembly 11. In the embodiment shown in FIG. 2the pressure barriers 38′ and 40′ extend radially outwardly from theaxle 12 and spindle 13 and are positioned adjacent the bearings 20, 22and brake drum 24. While any type of fusible plug is satisfactory, onesold under the trademark LEEKPRUF sold by the Mueller RefrigerationCompany, Inc. is satisfactory. Of course, other types of thermallyoperated valves (variously denoted by reference numbers 39, 39′, 39″, 39a, 39 b, 39 c, 39 d, 39 e and 39 f, and 41, 41′, 41″, 41 e and 41 f inFIGS. 10-18; all other reference numbers in FIGS. 10-18 denote the sameelements as described in connection with FIGS. 1-9) may be used foropening the air supply such as a thermally electric switch whichoperates an electric operated valve. While it is convenient to use thehollow axle 12 as part of the air supply, other types of air supplytubing could be provided.

Referring now to FIG. 3, another form of the present invention is shownwhich is similar to FIG. 2 with the exception that a heat sensitivepressure barrier or fusible plug 38 a is positioned in the end plug 37.This provides a simplified manufacturing and construction form, but yetthe heat sensitive pressure barrier and control, is mounted sufficientlyclose to the heat assembly 13 for measuring the temperature of the wheelhub assemblies 11.

Referring now to FIG. 4, still another form of the present invention isshown in which instead of the interior 42 of the axle 12 forming a partof the air pressure system includes air supply conduits or tubings 46and 48 connected between the air line 36 (FIG. 1) and the fusible plugs38 and 40, respectively.

Referring now to FIG. 5, another form is shown in which again the axle12 does not form an air supply but an air conduit or tubing 50 isconnected between the air line 36 (FIG. 1) and a fusible plug 38 b inthe end plug 37. The end plugs 37 in the embodiments of FIGS. 4 and 5serve the purpose of preventing debris in the inside of the axle 12.

While the warning system of FIGS. 1-5 provide a stand-alone system forvehicles such as trailer tractors, the warning system is particularlyand easily adapted for use with an automatic tire inflation system whichalready includes an air pressure supply and a warning system measuringthe loss of air pressure from the system or tires. Therefore, thecombination of the temperature warning system of the present inventionwith an automatic tire inflation system provides a means of informingthe vehicle operator of temperature problems. While the presentinvention can be used with various types of automatic tire inflationsystems, it is useful with the system shown in FIG. 6 and more fullydescribed and illustrated in patent application Ser. No. 10/186,951,entitled “Rotary Air Connection With Rearing For Tire Inflation System”which is hereby incorporated by reference. The reference numeral 100generally indicates the rotary air connection for supplying air from anair supply on a vehicle in an automatic tire inflation system for avehicle to the rotating tires. The numeral 112 generally indicates oneaxle or spindle, a hub cap 114 is provided at each end of the axle 112for retaining lubricant in the wheel bearings and an air supply 116,either directly in the axle 112, or through an interior conduit (notshown) in the inside of the axle 112 supplies air to the rotary airconnection through the inside of the axle. A pneumatic rotary uniongenerally indicated by the reference 120 is supported and positioned inthe center end of the axle 120, such as by force fit plug 220, butsealingly engages the interior of the axle 112 by a seal 124 if air isinjected directly into the inside of the axle 112. The rotary union 120has a first stationary part 128 having a passageway 136 therethrough.The passageway 136 is in communication with the air supply 116. A firstresilient rotary seal 138 is supported in the passageway 136 andencircles the passageway 136. The union 120 includes a second rotatablepart including a tabular member 142 having a first end 144 and a secondend 146. The second end 146 is coaxially extendable through and islongitudinally and rotationally movable in the passageway 136 andsealably engages the rotary seal 138 and is in communication with theair supply 116. The first end 144 of the tubular member 142 is sealablyconnected to the air connection or T-body 152 on the hub cap 144 througha seal 150. An air connection 152 or T-body is provided on the hub cap144 for connection to the tire or tires at the end of the axle 112. Theend 144 of the tubular member 142 includes a shoulder which includes abearing 101. In operation, air 116 is supplied through the stationarypart 128 of the rotary union 120. The hub cap 114 rotates with thewheels relative to the tubular member 142. The above-named descriptionis generally disclosed in U.S. patent application Ser. No. 10/186,951entitled “Rotary Air Connection With Rearing For Tire Inflation System”.

Thus, the automatic tire inflation system 100 of FIG. 6 already includesan air pressure supply 116 and any suitable warning system consisting ofa flow switch 32 a and a warning indicator light 34 a. The use of a heatsensitive pressure barrier 38 c at a location near the wheel bearings orbrake area on the spindle 113 provides a temperature warning system ofthe present invention. Again, if the spindle reaches a predeterminedtemperature the fusible plug melts releasing air from the air supply 116and actuates the warning system light 34 a for notification of theoperator. The operator can quickly determine whether the warning system34 a is indicating a pressure leak in the tires or a high temperatureproblem in the wheel hub area.

Referring now to FIG. 7, another form of the present invention is shownhaving an automatic tire inflation system of which only stationary part128 of the rotary connection is shown. In this form of the invention theair supply 116 is supplied through an internal conduit or tubing 150which supplies air to the passageway 136 in the member 128 and alsosupplies air to a heat sensitive pressure barrier or fusible plug 38 d.

Referring now to FIG. 8, a further form of the present invention isshown including an automatic tire inflation system in which only thestationary part 128 of the rotary connection is shown. Again, in thisembodiment, the air supply 116 is supplied to an air tubing or conduit150 a inside of the axle 112 and is connected to the passageway 136 inthe part 128. Heat sensitive pressure barriers or fusible plugs 38 e and40 e are provided radially extending out of the axle 112 and areconnected to the air supply tubing 150 a by air tubes 152 and 154.

Referring now to FIG. 9, again, another form of the present invention isshown which includes an automatic tire inflation system in which onlythe stationary part 128 of the rotary connection is shown. In thisembodiment, the interior of the hollow axle 112 forms part of the airsupply for supplying air by 116 to the passageway 136. Again, heatsensitive pressure barriers or plugs 38 f and 401 are provided radiallyextending through the wall of the axle 112 or spindle.

Although the present invention and its advantages have been described indetail, it should be understood that various changes, substitutions andalterations can be made herein without departing from the invention asdefined by the appended claims. Moreover, the scope of the presentapplication is not intended to be limited to the particular embodimentsof the process, machine, manufacture, composition, or matter, means,methods and steps described in the specification. As one will readilyappreciate from the disclosure, processes, machines, manufacture,compositions of matter, means, methods, or steps, presently existing orlater to be developed that perform substantially the same function orachieve substantially the same result as the corresponding embodimentsdescribed herein may be utilized. Accordingly, the appended claims areintended to include within their scope such processes, machines,manufacture, compositions of matter, means, methods or steps.

1-16. (canceled)
 17. A vehicle trailer wheel-end assembly comprising: awheel-end component mounted at the end of a hollow trailer axle, saidhollow trailer axle being capable of including pressurized air; and avalve mounted to said hollow trailer axle near said wheel-end component,said valve being capable of receiving heat from said wheel-end componentand being capable of releasing said pressurized air.
 18. The vehicletrailer wheel-end assembly of claim 17, said valve is capable ofreleasing said pressurized air upon said valve reaching a predeterminedtemperature.
 19. The vehicle trailer wheel-end assembly of claim 18,wherein said valve is configured to emit a noise when releasing saidpressurized air, said noise capable of being audible to a driver of avehicle pulling a trailer using said wheel-end assembly.
 20. The vehicletrailer wheel-end assembly of claim 18, wherein said valve comprises afusible material.
 21. The vehicle trailer wheel-end assembly of claim17, wherein said valve is a fusible plug.
 22. The vehicle trailerwheel-end assembly of claim 21, wherein said fusible plug comprises aeutectic alloy.
 23. The vehicle trailer wheel-end assembly of claim 17,wherein said hollow trailer axle is sealed to contain said pressurizedair.
 24. The vehicle trailer wheel-end assembly of claim 17, whereinsaid hollow trailer axle includes a conduit for communicatingpressurized air to said valve.
 25. The vehicle trailer wheel-endassembly of claim 17, wherein said wheel-end component comprises atleast one of a bearing, a brake drum, a brake disk, a wheel hub and awheel. 26-33. (canceled)
 34. A vehicle trailer wheel-end assemblycomprising: a wheel-end component mounted at the end of a hollow traileraxle, said hollow trailer axle capable of including pressurized air; anda valve capable of releasing said pressurized air upon said valvereaching a predetermined temperature.
 35. The trailer vehicle wheel-endassembly of claim 34, wherein said valve is configured to emit a noiseof predetermined frequency when releasing said pressurized air.
 36. Atrailer vehicle wheel-end assembly comprising: a wheel-end componentmounted at the end of hollow trailer axle, said hollow trailer axlebeing capable of including pressurized air; a heat sensor mounted in aheat-exchange relationship with a wheel-end component; and a valvemounted to said hollow trailer axle and connected to said heat sensor,said valve being capable of opening to release said pressurized air whensaid heat sensor reaches a predetermined temperature due to heatreceived from said wheel-end component.
 37. The vehicle trailerwheel-end assembly of claim 36, wherein said heat sensor comprises athermal electric switch.
 38. The vehicle trailer wheel-end assembly ofclaim 36, wherein said heat sensor comprises a thermocouple.
 39. Thevehicle trailer wheel-end assembly of claim 36, wherein said heat sensorcomprises a thermistor.
 40. The vehicle trailer wheel-end assembly ofclaim 36, wherein said heat sensor comprises a heat-sensitive wire. 41.The vehicle trailer wheel-end assembly of claim 36, wherein said valveis electrically-operated. 42-46. (canceled)
 47. The vehicle trailerwheel-end assembly of claim 36, wherein said connection between saidvalve and said heat sensor is wireless.
 48. (canceled)